1. Field of the Invention
The present invention relates to a loop bin for use in a tape transport arrangement, particularly to a loop bin for use in contact printing tape transport arrangements that can transport an endless magnetic tape and contain it in a zigzag line in its course of transportation.
2. Description of the Prior Art
Widespread use of home video recording and playback equipment has increased the demand for prerecorded cassettes, especially half-inch video cassettes. Fast production of such cassettes is difficult, because video signals contain a large amount of information which must be reproduced with a high degree of accuracy to maintain adequate image and color standards.
At present, the preferred video recording method used by this industry is to use upward of 1,000 recording machines, all operating simultaneously, all receiving a realtime signal from one master playback machine to produce multiple copies. The logistics of providing, loading, unloading, operating and maintaining such multitude of relatively complex equipment makes reproduction a very expensive process.
Another approach to magnetic recording duplication is non-realtime duplication known as magnetic replication. In this type of duplication, the signal pattern from a master tape is replicated directly on the receiving tape at very high speed. The magnetic pattern in this process is copied onto a receiving tape in much the same way as a visible image is printed through a high speed press onto a sheet of paper. As a result, the term contact printing has sometimes been used to designate a process of transferring information contained in one recording medium to a second recording medium directly, without an intermediate step of generating an electrical signal. Copy speeds in excess of 100 times realtime duplication have been reported.
A tape replication technique has been developed as a method for duplicating a recorded tape on which a signal was recorded earlier (hereafter referred to as a master tape) onto a blank tape on which no signal has been recorded (hereafter referred to as a copy tape). When this tape replication technique is implemented, the magnetic medium surface of a master tape is pressed toward the magnetic medium surface of a copy tape, and an external magnetic field or heat is applied to an overlapping area. As a result, a reversed image (i.e., mirror image) of the signal recording pattern recorded on the master tape is formed on the magnetic medium surface of the copy tape, and the duplication is thus completed. If the aforementioned transfer duplication technique is implemented, duplication can be carried out quite efficiently even if video tapes and PCM recording tapes on which complicated signal recording patterns have been impressed are employed, since the transfer is carried out by simultaneously transporting the master tape and copy tape.
It is desirable to use a system which does not require a step of rewinding the master tape after it has been recorded once. For this purpose the master tape should be made of an endless loop. An example of arrangements for transporting such an endless-loop master tape was disclosed in a Japanese Utility Model Laid-Open Publication No. 54-72513. In this arrangement, a loop bin is provided virtually perpendicular to a panel base so as to contain the master tape in a zigzag line in parts of the transport course. U.S. Pat. Nos. 4,213,159 and 4,698,701 each disclose a tape transporting device wherein the front and rear ends of a master tape are connected to form an endless loop and a copy tape is transported between a pair of reels, i.e., a feeding reel and a winding reel. In these arrangements, the endless master tape is continually fed into a loop bin and is piled on top of itself in an overlapping or zigzag fashion. This creates a problem. The lower part of the master tape piled at the bottom of the loop bin can become creased and distorted since the lower part of the piled tape cannot endure the weight of the upper piled part of the master tape. The problem is particularly noticeable in tape duplication systems. This is because the copy tape is produced as the master tape is distorted.
An object of the present invention is to provide an improved loop bin for an endless master tape in a contact printing system that minimizes the above-mentioned defects.